Showing a house when not in the same city/state?

[Mariajose Hidalgo]

Hi everyone, I have a quick maybe weird question... My husband and I have a rent-to-own property in a different state and we are trying to figure out a way to show it without having anyone there.  The house is in a very small town and we have been getting a lot of inquiries but for some reason or another people don't seem to be able to show up when we have the open house.  We have a lockbox there, and my husband figured if we got a picture of the driver's license of the person trying to see it, then we should be good giving them the lockbox code and them going into the house.  I, on the other hand, feel I need a little bit more, like something in writing from that person that says they will not give the code to anyone and that if something is not left locked properly and the house is broken in because of that, then they would be held liable or something of the sort.

I remember that there are people who do this, but I don't remember if there is a name or there is an example of said "addendum" for it.  Help?